Use of carboxymethyl cellulose(cmc) in fruit-based products

ABSTRACT

The invention relates to the use of a carboxymethyl cellulose (CMC) for preparing fruit-based products, such as jams including low calory jam, fruit preserves, pie fillings, fruity sauces, fruity fillings in cookies, fruit-based toppings, or beverages, wherein the CMC is characterized by forming a gel at 25° C. after high-shear dissolution in a 0.3 w % aqueous sodium chloride solution, the final content of the CMC in the aqueous sodium chloride solution being 1 wt % for a CMC having a degree of polymerization (DP) of &gt;4,000, 1.5 wt % for a CMC having a DP of &gt;3,000-4,000, 2 wt % for a CMC having a DP of 1,500-3,000, and 4 wt % for a CMC having a DP of &gt;1,500, the gel being a fluid having a storage modulus (G′) which exceeds the loss modulus (G″) over the entire frequency region of 0.01-10 Hz when measured on an oscillatory rheometer operating at a strain of 0.2. The CMC may also be used in combination with hydrocolloids such as carrageenan, starch, alginates, xanthan, konjac, or food protein.

The present invention relates to the use of carboxymethyl cellulose infruit-based products.

Carboxymethyl cellulose (CMC), typically in the form of sodiumcarboxymethyl cellulose, is a well-known water-soluble polymer which iswidely used in food products. Until now the use of conventional CMC infruit-based products has been limited due to the slimy and stickymouthfeel or insufficient gelling properties.

Several prior art documents disclose the use of conventional CMC infruit-based products.

Japanese patent publication JP 080-38076 discloses the combined use oftwo kinds of CMC as thickener in jams. Of the two CMCs one has a lowviscosity and the other has a relatively high viscosity of from 1,000 to20,000 mPa·s for a 2 percent by weight (wt %) aqueous solution. Thelow-viscosity CMC serves to hold down water release, whereas thehigh-viscosity CMC is present to improve the gelling properties of thejam. Despite this improvement, the jams containing these CMCs stillrequire an undesirably large total amount of CMC exceeding 1 wt %. Theselarge amounts of CMC result in a very sticky mouthfeel of the jams.

In U.S. Pat. No. 3,418,133 the use of a CMC in fruit-based products,such as orange flavoured spreads or fruit deserts, is described. VariousCMCs are disclosed having a viscosity varying from about 10 mPa·s for a2% solution to 42,000 mPa·s for a 1% solution. All CMCs have a degree ofsubstitution (DS) of between 0.1 and 0.6, which make them generally lesssuitable in aqueous media due to their relatively low solubility. It isfurther noted that U.S. Pat. No. 3,418,133 discloses examples offruit-based products in which a relatively large amount of CMC, i.e.exceeding about 3 wt %, is used. Use of such large amounts of CMC isundesirable. In low pH environments (i.e. acidic environments) typicalfor fruit-based products, the solubility of these CMCs is insufficient.Such undesirable incomplete dissolution of the CMC generally results ina sandy mouthfeel of the fruit-based product.

In the above-described prior art documents the CMCs described are notcapable of forming a gel at a dosage level and conditions typical forthis product.

As a result of the fact that conventionally used CMCs are not capable offorming a gel, nowadays other thickening agents such as pectin, guar orstarch are preferred over CMC.

Hence, there is a need in the art for a CMC which can be usedadvantageously in fruit-based products and which does not have thedisadvantages mentioned above.

The present invention relates to the use of a carboxymethyl cellulose(CMC) for preparing fruit-based products, wherein the CMC ischaracterized by forming a gel at 25° C. after high-shear dissolution ina 0.3 wt % aqueous sodium chloride solution, the final content of theCMC in the aqueous sodium chloride solution being 1 wt % for a CMChaving a degree of polymerization (DP) of >4,000, 1.5 wt % for a CMChaving a DP of >3,000-4,000, 2 wt % for a CMC having a DP of1,500-3,000, and 4 wt % for a CMC having a DP of <1,500, the gel being afluid having a storage modulus (G′) which exceeds the loss modulus (G″)over the entire frequency region of 0.01-10 Hz when measured on anoscillatory rheometer operating at a strain of 0.2.

The definition of a gel can also be given in terms of the loss angle,delta, which can be calculated from the formula: G″/G′=tan delta. TheCMC to be used in accordance with the present invention has a deltasmaller than 45°.

Apparatus for high-shear dissolution are known to a person of ordinaryskill in the art. High-shear dissolution typically is achieved by usinga Waring blender or Ultra-Turrax. These apparatus typically operate atapprox. 10,000 rpm or more.

The use of a CMC in accordance with the present invention in fruit-basedproducts unexpectedly leads inter alia to an improvement in gellingproperties, flowing properties, consistency, and stability. By the useof these CMCs fluid loss or syneresis can be prevented. These CMCsfurthermore are soluble in both hot and cold water. This is advantageousover e.g. pectin, as the CMC is dissolved without requiring additionalheating, leading to a significant saving of energy and a reduction ofcosts related thereto.

At high temperatures the gelling properties remain unimpaired, avoidingflotation of fruit particles and resulting in a uniform distribution offruit. A further advantage is that the use of CMCs according to theinvention does not require a minimum level of soluble solids (e.g.sugar) as opposed to for example pectin. Consequently, the CMC accordingto the invention is suitable for use in fruit products which comprise alow amount of sugar or are even free of sugar.

In the context of the present product, the abbreviation CMC stands forcarboxymethyl cellulose as well as for sodium carboxymethyl cellulose.

It is further appreciated that in fruit-based products various types offruit, fruit pulp, fruit concentrate, fruit juice, dried fruit particlesor synthetic fruity additives which taste or smell like fruit are used.In the context of the product, the term “fruit” refers to both freshfruit and fruity additives, which are commonly known in the art.

The CMC to be used in accordance with the present invention can beobtained by the processes described by D. J. Sikkema and H. Janssen inMacromolecules, 1989, 22, 364-366, or by the process disclosed in WO99/20657. The procedures and apparatus to be used are conventional inthe art and variations on these known procedures can easily be made by aperson skilled in the art using routine experimentation. In particular,we have found that the amount of water which is used in the process isan important parameter for obtaining the CMC in accordance with thepresent invention. Typically, a 20-40 wt % (final content) aqueousalkali metal hydroxide solution (e.g. aqueous sodium hydroxide solution)is used.

The characterization of CMCs depends mainly on rheology measurements, inparticular viscosity measurements. See, e.g., J. G. Westra,Macromolecules, 1989, 22, 367-370. In this reference, the properties ofthe CMCs obtained via the process disclosed by Sikkema and Janssen inMacromolecules, 1988, 22, 364-366, are analyzed. Important properties ofa CMC are its viscosity, thixotropy, and shear-thinning effect.

The rheology of aqueous CMC solutions is rather complex and depends on anumber of parameters including the degree of polymerization (DP) of thecellulose, the degree of substitution (DS) of the carboxymethyl groups,and the uniformity or non-uniformity of substitution, i.e. thedistribution of carboxymethyl groups over the cellulose polymer chains.

The degree of polymerization (DP) of the CMC to be used in accordancewith the present invention can vary over a broad range. It is noted thatwith the term “degree of polymerization” a skilled person willunderstand that this term refers to the average degree ofpolymerization. In the context of the present invention, a distinctionis made between the following DP ranges, i.e. >4,000, >3,000-4,000,1,500-3,000, and <1,500. Typically, the CMC is prepared from linterscellulose (DP typically >4,000-7,000), wood cellulose (DP typically1,500-4,000) or depolymerized wood cellulose (DP typically <1,500).Preferably, the DP of the CMC to be used in accordance with the presentinvention is from 1,500 to >4,000, more preferably >3,000, even morepreferably >4,000. It is preferrred that the CMC is prepared fromlinters cellulose.

The CMC to be used in accordance with the present invention typicallyhas a DS of at least 0.6, preferably at least 0.7, and most preferablyat least 0.8, and typically of at most 1.2, preferably at most 1.1, andmost preferably at most 1.0.

The Brookfield viscosity (Brookfield LVF, spindle 4, 30 rpm, 25° C.) ismeasured after high-shear dissolution, for example using a Waringblender, of the CMC of the present invention in a 0.3 wt % aqueoussodium chloride solution, the final content of the CMC in the aqueoussodium chloride solution being 1 wt % for a CMC having a degree ofpolymerization (DP) of >4,000, 1.5 wt % for a CMC having a DPof >3,000-4,000, 2 wt % for a CMC having a DP of 1,500-3,000, and 4 wt %for a CMC having a DP of <1,500. Preferably, a CMC having a viscosity ofmore than 9,000, more preferably of more than 9,500, even morepreferably of more than 10,000 mPa·s, is used.

Aqueous solutions of the CMC to be used in accordance with the presentinvention are strongly thixotropic. The thixotropy can be determined bypreparing a 1 wt % aqueous CMC solution and measuring the viscosity as afunction of the shear rate (i.e. 0.01-300 s⁻¹) on a controlled rate orcontrolled stress rheometer in rotational mode at 25° C. using acone-plate, parallel-plate or bob-cup geometry. An upcurve is recordedin which the shear rate is increased from 0.01 to 300 s⁻¹ in 3 minutes,immediately followed by the recording of a downcurve in which the shearrate is decreased over the same range and time. For a CMC in accordancewith the present invention, the upcurve will be at a higher viscositylevel than the downcurve and the area between the two curves is ameasure for thixotropy, also referred to as the thixotropy area.Typically, one speaks of a thixotropic solution when the area has avalue of 5 Pa·s·s⁻¹ or more when measured at 2 to 4 hours afterpreparation of the aqueous solution.

Without being bound by theory, it is believed that the above-mentionedrheological properties are due to the presence of poorly ornon-substituted parts (i.e. hardly any or no carboxymethyl substitutionon that part of the cellulose) and of significantly more highlysubstituted parts of the CMC according to the invention. The low ornon-substituted parts interact with each other leading to the formationof a gel of the CMC according to the invention. The particulardistribution of carboxymethyl groups over the CMC is encountered to amuch smaller extent in conventional CMCS. For this reason conventionalCMCs, which are not in accordance with the present invention, do notexhibit the rheological properties of the CMCs according to theinvention.

The CMC of the present invention can be used in a wide variety offruit-based products. Preferred fruit-based products are jams includinglow calory jams, fruit preserves, pie fillings, fruity sauces, fruityfillings in bakery products (such as cookies and cakes), fruit-basedicings or toppings, jellies, sweets, and beverages comprising fruitincluding dairy-based and alcohol-containing drinks. Particularlypreferred fruit-based products are jams and fruity sauces.

Any type of fruit known in the art is suitable for use in the presentinvention. Examples of such fruits are citrus fruit, apple, pear,blueberry, strawberry, cherry and exotic fruits such as passion fruit ormango.

We have found that it can be advantageous to use a CMC in accordancewith the present invention in combination with another hydrocolloidhaving gelling or binding properties, such as pectin, carrageenan,starch, alginate, xanthan, konjac, locust bean gum, guar gum, or foodprotein, for example casseine, soja and gelatine. Also combination of aCMC in accordance with the invention and two or more of thehydrocolloids are envisaged. It is noted that some of thesehydrocolloids are already applied as sole thickener in commonfruit-based products. For example, in jams pectin, which is relativelyexpensive, is used. The pectin can be replaced partially or completelyby the CMC in accordance with the present invention. As CMC is lessexpensive than pectin, the thickener will become cheaper. It is alsoenvisaged to replace the pectin with a combination of CMC and anotherhydrocolloid. Combinations of the CMC of the invention andkappa-carrageenan or alginate are most preferred.

The CMC of the invention is capable of forming a gel in an acidicenvironment. Typically, the CMC is able to form a gel at a pH of atleast 1, preferably at least 2, and most preferably at least 2.5, and apH of at most 6, preferably at most 5, and most preferably at most 4.5.This property makes these CMCs suitable for fruit-based products, asthese are generally acidic in nature.

Preferably, the CMC is gelated by exposing the CMC to a high shear (asdescribed in the Examples). Applying a high shear improves the gellingproperties of the CMC considerably.

The gelling properties of the CMC of the present invention can also beimproved by a heat treatment. Preferably, the CMC is treated at 50° C.or higher, more preferably at 60° C. or higher and most preferably at70° C. or higher.

The amount of CMC to be used in accordance with the present inventionvaries and is dependent on the amount and the type of fruit, water, andother additives used for preparing a fruit-based product. Typically, anamount of at least 0.05 wt %, preferably at least 0.1 wt %, mostpreferably at least 0.2 wt %, and at most 2 wt %, preferably at most 1.5wt %, most preferably 1 wt %, is used, based on the total weight of thefruit-based product. In general, we have found that compared to a CMCnot in accordance with the present invention, less of a CMC inaccordance with the present invention is required for preparingfruit-based products. The optimal amount of CMC to be used in accordancewith the present invention can be determined by a person skilled in theart by routine experimentation using the above amounts and the Examplesgiven below as guidance.

The CMC to be used in accordance with the present invention, if desiredcombined with other solid ingredients of the fruit-based product,typically is added as a dry powder, or as an aqueous solution.

Fruit-based products are prepared according to methods which are knownin the art. The skilled person will understand that fruit-based productsare prepared according to methods that are specific for each product.

The present invention is illustrated by the following Examples.

EXAMPLES

Materials

Akucell® AF 2985, Akucell® AF 3185, and Akucell® HF 300 (all ex AkzoNobel) are CMCs which are not in accordance with the present invention.

CMC-1 and CMC-2 are CMCs which are in accordance with the presentinvention, i.e. they form a gel at 25° C. when dissolved in an amount of1 wt % under high shear in a 0.3 wt % aqueous sodium chloride solution.

CMC-1: Prepared from linters cellulose. DP of 6,500. DS of 0.85. A 1 wt% aqueous solution of this product has a Brookfield viscosity of 8,500mPa·s using a Heidolph mixer at 2,000 rpm and of 8,000 mPa·s using aWaring blender at 10,000 rpm (i.e. high shear). CMC-1 has apseudoplastic rheology and a tendency to thicken up in time, that is, ithas a thixotropic rheology. A thixotropy area of 40 Pa·s·s⁻¹ wascalculated using the method described hereinbelow.

CMC-2: Prepared from linters cellulose DP of 6,500. DS of 0.75. A 1 wt %aqueous solution of this product has a Brookfield viscosity of over12,000 mPa·s using a Heidolph Mixer at 2,000 rpm and of well over 20,000mPa·s using a Waring Blender at 10,000 rpm. (i.e. high shear). CMC-2 hasa pseudoplastic rheology and a tendency to thicken up in time, that is,it has a strong thixotropic rheology. A thixotropic area of more than250 Pa·s·s⁻¹ was calculated using the method described below. CMC-2 doesnot dissolve in a salt or acid solution under normal mixing conditions(i.e. propellor blade mixer at 2,000 rpm). At high shear (i.e. WaringBlender at over 10,000 rpm) CMC-2 only dissolves when low wt % of saltand/or acid are used.

Rheology

CMC (final content 1 wt %) was dissolved under high shear in a 0.3 wt %aqueous sodium chloride solution using a Waring blender. Afterdissolution, the fluid or gel was brought to 25° C. The storage modulus(G′) and the loss modulus (G″) of the fluid were measured as a functionof the oscillation frequency (i.e. 0.01-10 Hz) on a TA Instruments AR1000 controlled stress rheometer operating at a strain of 0.2 (i.e. 20%)in oscillation mode using a 4″-cone-plate geometry at a temperature of25° C.

Viscosity

The viscosity of a 1 wt % aqueous solution of CMC was measured using aBrookfield LVF viscometer, spindle 4, 30 rpm, 25° C.

Thixotropy

For determining the thixotropy, a 1 wt % aqueous CMC solution wasprepared and the viscosity was measured as a function of the shear rate(i.e. 0.01-300 s⁻¹) on a controlled stress rheometer in rotational modeat 25° C. using a cone-plate. An upcurve was recorded in which the shearrate was increased from 0.01 to 300 s⁻¹ in 3 minutes, immediatelyfollowed by the recording of a downcurve in which the shear rate wasdecreased over the same range and time. The measurement was carried outat 2 to 4 hours after preparation of the aqueous solution.

Example 1

In Example 1, various strawberry jams were prepared with variousthickeners. As thickeners were used Akucell® HF 300, Akucell® AF 2985,Akucell® AF 3185, Genu Pectin A (medium-rapid set), and Genu PectinLM-105 AS (both pectins ex CP Kelco), which are not in accordance withthe invention, and CMC-1 (which is in accordance with the invention).Also jams were made wherein pectin was mixed with either CMC-1 orAkucell® AF 2985, and used as thickener.

The jam was prepared by first mixing the thickener, citric acid, sodiumbenzoate, and three spoons of sugar. The dry mixture was subsequentlysprinkled over the strawberries, which after the addition of water wereheated and boiled for 1 minute. The remaining part of the sugar wasadded to the boiling mixture, and this boiling was continued until allthe sugar was dissolved. After dissolving of the sugar the obtained jamwas cooled. Irrespective of the type of thickener used, the jamcomprises 0.50 wt % thickener, 0.11 wt % citric acid, 0.02 wt % sodiumbenzoate, 41.92 wt % strawberries, 46.03 wt % sugar, and 11.42 wt %water.

In the Table below the different thickeners are presented with theircorresponding ability to form a gel in the acidic environment of the jamand their flowing properties. The flowing properties are represented bya number from 1 to 5, where 1 represents a self-flowing substance and 5represents a non-flowing substance. Further it is indicated in the Tablewhether the obtained jam reveals any flotation of fruit due to thehigh-temperature treatment. TABLE 1 Thickener Gel formation FlowingProperty Flotation Pectin LM-105 AS + 4.5 Yes Pectin A + 5 Yes HF 300 −1 Yes AF 3185 − 2.5 No AF 2985 − 3 No CMC-1 + 4 No Pectin/CMC-1 + 5 No(0.25 wt %/0.25 wt %)

It is noted that the jams which contain pectin all reveal the formationof foam, which is undesirable. Foam formation is not encountered whenonly CMC is used as thickener. Table 1 shows that all thickeners exceptfor Akucell® HF 300, Akucell® AF 2985 and Akucell® AF 3185 are capableof gel formation in the acidic environment of the jam. At the amountused, the jams with a (conventional) CMC thickener are self-flowing. Thejam containing CMC-1 reveals almost the same gel property as thepectin-containing jam. Combination of pectin and conventional CMC-1gives a flowing properties comparable to pectin itself. An advantage ofCMC-based thickeners (in accordance with the invention) as compared topectin is that they are more stable at higher temperatures and henceshow no flotation of fruit. The fruit in the CMC-containing jam remainswell-distributed throughout the jam, in contrast to the jam containingpectin.

It is further noted that the gel properties of the pectin-containing jamare not restored after deformation (i.e. when exposed to a high-shearstress), whereas the CMC-1 containing jam has unchanged gel propertiesafter deformation. Jams formulated with pectin suffer from syneresisover time. This phenomenon does not occur in CMC-containing jams.Finally, it is noted that the addition of CMC to a jam does not have anadverse effect on the taste of the jam.

Example 2

Pie fillings were prepared from preserved cherries on sugar syrup. Forthis experiment the cherries were separated from the syrup. The fillingswere prepared with 300 g cherries, 300 g cherry juice, 80 g sugar, andvarious thickeners. When CMC-1 was applied as thickener, the amount wasvaried from 1.0 wt % to 1.75 wt %, based on the total weight of the piefilling. For comparison, pie fillings were made with Instant Clearjel E(a starch ex National Starch), Paselli BC (a starch ex Abebe), andAkucell® AF 2985. The amount of the thickeners in the pie filling, aswell as their viscosity, is shown in Table 2.

It is noted that in this fruit-based product pectin is generally notused because pectin melts during a heating step. As a result a highamount of starch is used giving a less natural appearance and mouthfeel.

The pie fillings were prepared by first mixing sugar and the thickenerto form a dry powder mix. This powder mix was added gradually to thesyrup while the syrup was continuously stirred. After the mixture hadbeen added completely, the obtained suspension was stirred for another 5minutes, after which the cherries were added and the pie filling wasobtained.

About 120 g of this pie filling were put on a plate. The filling wasarranged in a circle having a diameter of about 10 cm. The plate withthe pie filling was then heated in an oven at 220° C. for 20 minutes.The diameter of the pie filling was again measured. An adequate piefilling should not flow during the baking step. Also the mass lostduring the heating procedure was determined. The resulting diameters andmass losses are presented in the Table below. TABLE 2 Mass Viscositylost Diameter Diameter Thickener Conc. (%) (mPa.s) (%) start (cm) end(cm) Clearjel E 5.0 3,800 9.0 10 10.5 Paselli BC 5.0 5,800 11.7 10 11 AF2985 1.0 6,300 22.1 11 16 AF 2985 1.5 >20,000 11.0 10 13 CMC-1 1.0 1,20019.4 11 14 CMC-1 1.25 6,700 18.6 11 13 CMC-1 1.5 >20,000 13.5 10 10.5CMC-1 1.75 >20,000 11.0 10 10.5

In Table 2 it is shown that it is possible to prepare a pie fillingwithout starch. Compared to starch, much less of CMC-1 is required toobtain a pie filling having a consistency similar to that of the piefillings made with the starches Clearjel E and Paselli. Moreover, the1.5 wt % and 1.75 wt % CMC-1-containing pie fillings show similar masslosses to the 5 wt % starch-containing fillings. It is also shown thatthe use of CMC-1 leads to a better consistency than the use of theconventional AF 2985, when applied in the same amount. It is furthernoted that none of the pie fillings treated at the applied temperaturereveal any spattering of fluid.

The pie fillings prepared with starch have a turbid and flat appearance.In contrast, the fillings prepared with CMC have a more naturalappearance, as they are transparent and shiny, and a better mouthfeeland taste.

Example 3

In this Example several gels were prepared with CMC-1 and CMC-2 added asthickeners. These gels are suitable for use in fillings for cookies.Optionally, fruit, fruity flavors or other commonly known additives maybe added to these fillings.

Solutions of CMC-1 and CMC-2 were prepared by dissolving 3 g of the CMCin 300 ml of demineralized water at room temperature while stirringvigourously using a Heidolph mixer. In this way, a 1 wt % CMC solutionis obtained which is referred to as a low-shear solution of CMC. Ahigh-shear CMC solution was obtained by additionally stirring thelow-shear solution with a Waring blender for two minutes.

The pH of the solution was brought to about 3.4±0.1 by adding 1.5 g ofcitric acid (0.5 wt %). The citric acid was dissolved either before orafter dissolution of the CMC. Solutions were prepared with a Heidolphpropellor mixer (low-shear method). Additionally solutions were treatedwith a Waring blender (high-shear method). This method results in fourgels for each CMC of which the preparation procedure, the viscosity, andthe consistency are presented in the Table below. TABLE 3 Gelling Citricacid Shear Viscosity agent addition method (mPa.s) Consistency CMC-1Before Low 3,700 Flowing After Low 8,650 Gel Before High 11,200 GelAfter High 11,200 Gel CMC-2 Before Low 39 Flowing After Low 5,200 Weakgel Before High 2,300 Flowing After High >20,000 Strong gel

From Table 3 it is clear that the addition of citric acid after the low-or high-shear treatment results in a gel with a higher viscosity, andhence better gelling properties. It is also shown that a high-sheartreatment leads to a gel with better gelling properties than a low-sheartreatment does.

Example 4

In this Example, gels of CMC-1 and Kappa-carrageenan (ex Eurogum) wereprepared by first dissolving CMC in cold water followed by dissolutionof the carrageenan at 70° C. The gels were compared to a gel comprisingpectin (Genu Pectin medium-rapid set), which was prepared at 90° C.After dissolution of the pectin sugar was added to an amount of 65 wt %,based on the total weight of the composition. The compositions of theprepared gels and their corresponding consistencies are presented inTable 4. TABLE 4 CMC-1 K-carrageenan Pectin Sugar Water Gel (%) (%) (%)(%) (%) Consistency A 0.25 0.25 — — 99.5 Rigid B 0.25 0.25 — 65 34.5Rigid C — — 0.5 — 99.5 Fluid D — — 0.5 65 34.5 Rigid

The results show that CMC-1 in combination with Kappa-carrageenan formsa rigid gel irrespective of the sugar content. By contrast, pectin onlyforms a rigid gel in the presence of a very high amount of sugar.

1. A fruit-based product that comprises carboxymethyl cellulose (CMC),wherein the CMC is characterized by forming a gel at 25° C. afterhigh-shear dissolution in a 0.3 wt % aqueous sodium chloride solution,the final content of the CMC in the aqueous sodium chloride solutionbeing 1 wt % for a CMC having a degree of polymerization (DP) of >4,000,1.5 wt % for a CMC having a DP of 3,000-4,000, 2 wt % for a CMC having aDP of 1,500-<3,000, and 4 wt % for a CMC having a DP of <1,500, the gelbeing a fluid having a storage modulus (G′) which exceeds the lossmodulus (G″) over the entire frequency region of 0.01-10 Hz whenmeasured on an oscillatory rheometer operating at a strain of 0.2. 2.The fruit-based product of claim 1, wherein the CMC has a Brookfieldviscosity of more than 9,000 mPa·s after high-shear dissolution in a 0.3wt % aqueous sodium chloride solution, the final content of the CMC inthe aqueous sodium chloride solution being 1 wt % for a CMC having adegree of polymerization (DP) of >4,000, 1.5 wt % for a CMC having a DPof >3,000-4,000, 2 wt % for a CMC having a DP of 1,500-3,000, and 4 wt %for a CMC having a DP of <1,500.
 3. The fruit-based product of claim 1wherein the pH of the fruit-based product is between 1 and
 6. 4. Thefruit-based product of claim 1, wherein the CMC has a DP of 1,500 ormore.
 5. The fruit-based product of claim 4 wherein the CMC is preparedfrom linters cellulose or wood cellulose.
 6. The fruit-based product ofof claim 1 wherein the CMC has a DS of 0.6 to 1.2.
 7. The fruit-basedproduct of claim 1 wherein the fruit-based product is a jam, a fruitpreserve, a pie filling, a fruity sauce, a fruity filling in bakeryproducts, a fruit-based topping, a beverage comprising fruit, a jelly ora sweet.
 8. The fruit-based product of claim 1 wherein the CMC is usedin combination with pectin, carrageenan, starch, alginate, xanthan,konjac, locust bean gum, guar gum, or food protein.
 9. The fruit-basedproduct of claim 1 wherein the CMC is used in an amount of 0.05 to 1.5wt %, based on the total weight of the fruit-based product.